Twistable tray type automatic ice maker with detachable tray



Aug. 30, 1966 P. DE VINCENT 3,259,139

TWISTABLE TRAY TYPE AUTOMATIC ICE MAKER WITH DETACHABLE TRAY Filed June 1, 1964 4 Sheets-Sheet 1 INVENTOR. Patsy De Vince/2f His Affom ey P. DE VINCENT 3,269,139 TWISTABLE TRAY TYPE AUTOMATIC ICE MAKER WITH DETACHABLE TRAY Aug. 30, 1966 4 Sheets-Sheet 2 Filed June 1, 1964 INYENTOR. Pa/sy Del/meant H119 Afforney Aug. 30, 1966 P. DE VINCENT 3,269,139

TWISTABLE TRAY TYPE AUTOMATIC ICE MAKER WITH DETACHABLE TRAY 4 Sheets-Sheet 3 Filed June 1, 1964 INYENTOR. Patsy 0e V/ncenf HIS Affomey Aug. 30, 1966 P. DE VINCENT TWISTABLE TRAY TYPE AUTOMATIC ICE MAKER WITH DETACHABLE TRAY 4 Sheets-Sheet Filed June 1, 1964 INVENTOR.

His After/ray United States Patent 3,269,139 T'vVISTABLE TRAY TYRE AUTOMATIC ICE MAKER WITH DETAQIIABLE TRAY Patsy De Vincent, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed June 1, 1964, Ser. No. 371,559 9 Claims. (Cl. 62l37) This invention pertains to refrigerating apparatus and more particularly to an ice maker or automatic freezer of the twisting, tilting tray type.

The twisting, tilting tray type of automatic freezer usually employs a plastic tray. These trays under some conditions of operation may take a permanent set or distortion which causes lack of uniformity of the cubes and other undesirable effects. Since such trays are ordinarily relatively inexpensive, it is desirable that any such tray taking a permanent set or distortion be replaced. However the replacement of such a tray may be difficult for users and especially housewives, and usually has required the calling of a Serviceman at considerable expense.

It is an object of this invention to provide an automatic freezer of the twisting, tilting tray type in which the tray may be easily removed and replaced.

It is another object of this invention to provide an automatic freezer of the twisting, tilting tray type in which the tray can be replaced without removing the automatic freezer from the cabinet.

It is another object of this invention to provide an automatic freezer of the twisting, tilting tray type in which the tray is provided with an improved inexpensive efiicient sensing control for detecting the completion of the freezing of its contents.

It is another object of this invention to provide an automatic freezer of the twisting, tilting tray type in which a collecting bin is provided for collecting the frozen contents of the tray and in which the collecting bin is provided with a simple resilient support means which cooperates with the control of the automatic freezer to stop its operation when the bin is filled.

These and other objects are attained in the form shown in the drawings in which the ice tray is provided with a curled flexible rim at the opposite ends which fits into a novel holding arrangement in the supporting brackets at each end. The rear supporting bracket is mounted upon a straddle mounted pivot pin which is accessible from and removable from the front and which is held in place by removable fastening means such as a removable cotter pin or key. The tray is provided with a thermostatic detector to detect the completion of freezing which is in the form of a thermistor which is held against the exterior wall of one of the compartments of the tray by a foamed insulator which is molded to the exterior con tour of the compartment of the tray and has a recess for the thermistor and connecting wiring. The foamed insulator is heldin place be integral extruding pins extending from the compartment of the tray through apertures in the foamed insulator which are provided with rivet heads at their ends. A collector bin is provided beneath the tray for receiving the frozen contents of the tray upon the ejection thereof. This collecting bin is provided with a spring mounting arrangement. The bin cooperates with a control means which is effective to stop the operation of the automatic freezer when the contents of the bin have sufficient weight to deflect the resilient support for the bin.

Further objects and advantages of the present invention will be apparent from the following description,

reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown.

In the drawings:

FIGURE 1 is a vertical sectional view through a lower portion of a household refrigerator containing an automatic freezer or ice maker embodying one form of my invention;

FIGURE 2 is a top view of the automatic freezer shown in FIGURE 1;

FIGURE 3 is a vertical sectional view taken along the lines 33 of FIGURE 2;

FIGURE 4 is a fragmentary enlarged vertical sectional view of the rear support arrangement for the tray, slightly simplified, showing the first step in the connection of the tray to its rear support or alternatively the last step in the removal of the support from the tray;

FIGURE 5 is a fragmentary enlarged sectional view similar to FIGURE 4 but showing the second step in connecting the rear support to the rear of the tray or alternately the second step in removing the tray support from the tray.

FIGURE 6 is a fragmentary enlarged vertical sectional view showing the rear tray support in place on the tray together with the supporting pivot pin straddle mounted;

FIGURE 7 is a fragmentary vertical sectional view showing the collecting bin in filled position and the con trol switch cooperating with the collecting bin; and

FIGURE 8 is a wiring diagram of the apparatus.

Referring now to the drawings and more particularly to FIGURE 1, there is shown a household refrigerator 20 having an upper above freezing compartment 22 and a lower below freezing compartment 24. The upper compartment 22 is provided with an insulated door 26 and the lower compartment 24 is provided with an insulated door 28. The two compartments are separated by an insulated horizontal dividing wall 30. Beneath the compartment 24 is a horizontal insulated wall 30 forming the top of the machinery compartment 32 containing a sealed motor compressor unit 34 which withdraws evaporated refrigerant from the evaporator 36 and forwards the compressed refrigerant to a condenser 38 which condenses the compressed refrigerant and forces the condensed refrigerant through a capillary supply restrictor 40 back to the evaporator 36. The refrigerating system is operated so as to keep the evaporator 36 at a relatively cold temperature such as between about +5 F. and 10 F. The refrigerator may, for example, be like that shown in Patent No. 2,912,834 issued November 17, 1959.

The evaporator 36 is located beneath the false bottom wall 42 of the compartment 24 providing an evaporator compartment 44 having an entrance 46 at the front ad jacent the bottom of the door 28 through which air is withdrawn from the compartment 24. The rear of the evaporator compartment 44 behind the evaporator 36 is connected to the inlet of a fan 48 which is driven by an electric motor 50. This fan delivers the cold air through a duct 52 having an outlet 54 at the top which discharges cold air over the freezing tray 56 of an automatic ice maker or freezer 58 supported in the top of the compartment 24.

The automatic freezer has at the front end a mechanism housing 60 containing an electric drive motor 62 which drives a commutator 64 as well as mechanical mechanism for twisting and tilting the tray 56 to eject the frozen contents thereof. This mechanism may be of any suitable type, for example, like that shown in the Nelson Patent No. 2,942,436 issued June 28, 1960. The commutator 64 is provided with a third continuous conductor ring 66 which connects directly to the remaining conductor rings for current supply thereto and cooperates with a spring contact 6 8 connecting with the supply conductor L-1. l'The commutator 64 is also provided with an inner conductor ring 70 cooperating with a spring contact 72 connecting through the conductors 74 and 76 with the motor 62 having a second terminal connected through the conductor 78 with the supply conductor L-2. The motor is also controlled through a conductor 80, relating switch 82 and a conductor 84 which provides a shunt arrangement shuntingthe commutator rings 66 and 76 and their spring contacts 68 and 72.

The commutator 64 is also provided with a second conductor ring 86 cooperating with a spring contact 88 con necting through the conductor 90 with the solenoid coil of a water Valve 92 having its second terminal connecting through the conductor 94 with the supply conductor L-2. The automatic freezer is provided with a water or liquid supply pipe 90 provided with a manual control valve 98 controlling the flow through the pipe 121 and the pipe 123 extending through the insulating wall 30 to the discharge spout 125 supported on a bracket 127 extending from the mechanism housing 60 as shown in FIGURE 1. The solenoid valve 92 is located between the pipes 121 and 123.

The mechanism housing 60 is connected to a frame 129 which is mounted by screws to the adjacent sidewall of the compartment 24. The rear portion 131 of this frame is provided with an arm 132 terminating in an offset forwardly extending transverse projection 133 having an aperture therein which is aligned with an aperture 135 in the rear portion 131 to receive a straddle mounted pivot pin 137 which has its head 161 at the front and passes through and supports the rear supporting bracket 139 of the ice tray 56. The front supporting bracket 141 and the rear supporting bracket 139 are similar and have a peculiar shape. The rear one differs from the front one in that it has a circular aperture for receiving the rear pivot pin 137 while the front bracket 139 has a fiat sided aperture which receives the flat sided end portion 143 of the drive shaft 145 for the tray 56. The drive shaft 145 is driven from the electric drive motor 62 through the twisting and tilting mechanism.

The tray supporting brackets 139 and 141 each have a pair of lower curled portions 147 each of which terminates in a sharp edge 149. The tray 56 has for its edge portion a flat top rim 151 extending substantially completely around it which is connected to the adjacent peripheral, vertical wall portions of the compartments 154 of the tray 56. The compartments along the outer sides may have longitudinal ribs between them to improve the twisting of the tray. The tray 56 is made up of a relatively flexible resilient plastic material such as linear polyetheylene substantially uniform in thickness throughout. The portion 147 of the support 139 is curled first 180 in a comparatively large radius and thence is curled 160 in a smaller radius to the edge 149. The edge 149 is substantially square with a sharp edge. This edge 149 is spaced away from the straight naturally vertical portion or side 153 of the support 139, a distance substantially equal to the wall thickness of the tray 56. The support 139 also has a laterally extending projection 155 extending substantially perpendicular to the straight vertical portion 153 and spaced away from the outer periphery of the curled portion 147, a distance substantially equal to the wall thickness of the tray 56. The rim 151 of the tray 56 has a downwardly turned flange portion 157 extending substantially perpendicular to the flat top of the rim 151 with the inner section making a substantially sharp right angle bend. To attach the support 139 to the tray 56, the downwardly turned flange 157 is inserted between each cu-rled projection 147 and each right angle projection 155 as shown in FIGURE 4 and then the support 139 is turned counterclockwise as shown in FIG- URES 4 and until the flange 157 passes between the edge 149 and the straight vertical portion 153 to the position shown in FIGURE 6. As shown, the sharp bent portion between the downwardly turned flange 157 and the fiat topped portion 151 of the rim is spread as it passes through the position shown in FIGURE 5 intermediate the position shown in FIGURES 4 and 6. When the rim 151 is in the position shown in FIGURE 6, its flat top will be held against the right angle projection 155 firmly since the sharp right angled bend connecting with the downwardly turned flange 157 will resist the pulling of the rim 151 away from the curled portion 147 by reason of the fact that the flat portion of the rim 151 and the downwardly flange 157 must bend as illustrated in FIGURE 5 to accomplish its removal. The sharp edge 149 also tends to dig into the surface of the plastic to assist in preventing its accidental removal.

The same arrangement is provided in the support 141 and its connection with the front end of the tray 56. This arrangement therefore provides an easy means of connecting the supports 139 and 141 to the tray 56 without the use of any tools. The tray 56 can be readily removed by removing the cotter key 159 from the pivot pin 137 which allows the head 161 of the pivot pin 137 to be engaged and pulled forwardly completely out of the rear portion 131 and the support 139 and also if necessary or desired from the front perforated support 133. This frees the support 139 so as to permit free movement of the tray 56 sufiiciently to remove the support 141 from the end 1 43 of the shaft 145 so that the tray 56 can be removed easily with its supports. The two supports 139 and 141 can then be removed from the tray 56 by reversing the process illustrated in FIGURES 4 to 6. The rim 151 is thereby freed from the supports 139 and 141 without the use of tools. A new tray can then be obtained and the supports 139 and 141 may be attached thereto by using the process illustrated in FIGURES 4 to 6. After this the support 141 is then applied along with the tray 56 to the end 143 of the shaft 145 and the bracket 139 along with the opposite end of the tray 56 is held with the aperture in the bracket 139 in alignment with the aperture and the aperture in the bracket 133 so that the pivot pin 137 may be reinserted in the position shown in FIGURES 2, 3 and 6.

The projection 133 serves as a stop to limit the movement of the rear end of the tray in one direction so that the turning of the shaft 145 will twist the tray 56 to loosen the frozen cubes or pellets in the tray 56. The tray 56 is then turned as a unitary body preferably in the opposite direction until it is turned at least 90 from the horizontal to dump the cubes from the tray. The tray 56 may be further twisted in this position with the support 139 against a second stop until all the cubes are dislodged. After this, the mechanism driving the shaft returns the tray to the horizontal position for refilling.

The refilling is controlled by the ring 163 of the commutator 64 in cooperation with the contact 88, which energizes and opens the solenoid water valve 92 for a time sufiicient to fill the tray 56. After the refilling, the motor 62 is stopped when the commutator 64 turns the nonconducting gap between the ends of the conductor strip 70 into contact with the contact 72 to break the normal supply circuit for the motor 62. The mechanism is therefore idle during the freezing of the liquid in the tray 56. The restarting of the motor 62 is under the control of an electrical circuit which may, for example, be of the type shown in FIGURE 8. For controlling this restarting, the commutator 64 is provided with a fourth conductor strip 163 which cooperates with a spring contact 165 to energize the voltage reducing transformer 167 having its second terminal connecting with the supply conductor L-2. One terminal of the low voltage winding 169 of the transformer 167 is connected through the bin switch 171, a diode rectifier 173, a first fixed resistance 175, a second fixed resistance 177 and a variable resistance 179 with one terminal of the solenoid coil 181 which when energized closes the solenoid switch 82. The second terminal of the solenoid coil 181 is connected to a parallel circuit ambient temperature compensating network incorporating a compensating thermistor 183 connected in parallel with a fixed resistance 185. The second terminal of the parallel circuit is connected by the conductor 187 to the second terminal of the low voltage winding 169.

To assure that the voltage in this detection circuit is substantially constant regardless of the line voltage, there is connected between the fixed resistances 175 and 177 one terminal of a Zener diode 189 and one terminal of a capacitor 191. The second terminals of the Zener diode 189 and the capacitor 191 are connected to the conductor 187. To cause the solenoid coil 181 to close, the relay switch 82, when the contents of the tray 56 have been frozen, there is connected through the conductors 220 and 222 a sensing thermistor 193 between the conductor 187 and the conductor 195 connecting the variable resistance 179 and the solenoid coil 181.

This thermistor 193 is held against the outer surface of a wall of the compartment 197 in a cavity in the foamed insulator 196 molded to enclose this center front compartment 197 of the tray 56. The bottom wall of the compartment 197 is provided with two integral projections 199 extending downwardly through the foamed insulator 196 and provided with rivet heads at their lower ends for holding the foamed insulator 196 riveted to the bottom wall of the compartment 197. The two integral projections 199 beneath the compartment 197 are located along the center line of the tray 56 substantially directly beneath the axis between the drive shaft 145 and the pivot pin 137. This location is substantially beneath the twisting axis of the tray and thereby minimizes the effect of the twist upon the projections 199 and their riveted heads as well as the foamed insulator 196. The foamed insulator 196 is also provided with a channel for connecting the two conductors 220 and 222 which connect with the conductors 195 and 187 as shown in wiring diagram in FIGURE 8. The foamed insulator 196 shields the compartment 197 sufficiently from the cold circulating air so as to assure that the compartment 197 will be the last to freeze. The foamed insulator 196 also assures that the thermistor 193 is substantially at the same temperature as the compartment 197. The thermistor 193 is selected to have a sharp increase in resistance as the temperature of the liquid in the compartment 197 is reduced below water freezing temperatures. This increase in resistance causes a greater flow of current through the solenoid coil 181 causing the switch 82 to be reclosed, thereby starting the motor 62. The operation of the motor 62 will then turn the commutator 64 until the contact 72 again engages the conducting portion of the strip 70 to assure continued operation of the motor 62.

Beneath the tray 56 is a plastic collector bin 224 having outwardly extending side flanges 226 supported upon the side rails 228 of the frame 129. At the rear, the flanges 226 are provided with downwardly extending projections 23!) which engage the side rails 228 to serve as pivots at the rear end of the bin 224. The front end of the bin 224 is resiliently supported upon a pair of springs 232 having their rear ends provided with an eyelet 234 fastened to the bin 224 and having their front portions provided with a helical spring 236 threaded onto screws 238 inside the handle 240 extending across the front of the bin 224. This provides a resilient support for the front end of the bin 224 in which the wire springs 232 rest upon the front portions of the rails 228. When the bin 224 is substantially filled, the weight of the frozen cubes Will be suflicient to deflect the springs 232 so that the front end of the bin will move downwardly until the coil portion of the spring 236 will be collapsed as illustrated in FIGURE 7. The mechanism housing 60 is provided with the switch 171 which is a slide-bar type arranged to be closed in the position shown in FIGURE 3 when its actuator 242 is held in an upper position. However, when the bin 224 is filled and the spring 234 is deflected, as shown in FIGURE 7, the spring 224 will move the actuator 242 downwardly thereby opening the switch 171 to prevent further operation after the motor 62 is stopped when the nonconducting portion of the first ring '70 of the commutator 64 reaches the nonconducting portion as shown in FIGURE 8. This will stop the operation of the freezer until the bin 22 4 is relieved of some or all of the frozen cubes therein.

The conductors 220 and 222 are preferably provided with a plug connection 246 with the conductors 195 and 187 so that the plug connection 246 can be removed before the tray 56 is removed as previously described. This freezer therefore provides a convenient and eflicient Way for the detection of the freezing of the tray as Well as a convenient method for removal of the tray from the freezer.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. An automatic liquid freezer including a mold having wall portions forming liquid holding compartments, means for freezing liquid in said mold, a temperature responsive means in contact with a wall portion adjacent one of said compartments, .an insulating member shaped to fit over and overlay said temperature responsive means and the adjacent wall portion and a major part of the wall portion of one of said compartments, and means responsive to the temperature of the temperature responsive means for ejecting frozen liquid from said mold.

2. A freezer according to claim 1 in which the mold has an integral extension extending through the insulating member provided with an external head for holding the insulating member in contact with the mold.

3. A mechanical device including a support having a laterally extending projection and a curled projection adjacent to but spaced from said laterally extending projection, said curled projection being curled toward said laterally extending projection, an upwardly extending wall portion between said projections spaced from said curled projection, and a member of resilient material having an edge portion extending between said projections and around said curled projection and between said curled projection and said wall portion.

4. A device according to claim 3 in which the curled projection has a sharp edge extending against the portion of said edge portion extending between said curled projection and said wall portion.

5. A mechanical device including a support having an upwardly extending wall portion and a laterally extending projection extending from said wall portion and an upwardly curled projection extending substantially in the form of a spiral of unbroken curvature from said wall portion beneath and spaced from said laterally extending projection, and a member of resilient material having an upwardly extending wall portion provided with a rim extending laterally between said projections and downwardly between said curled projection and the upwardly extending wall portion of said support.

6. A mechanical device including a support means having a rear portion, a mold having a rear portion provided with a first aperture, the rear portion of said support means having a second aperture and also having a. forwardly extending projection provided with a third aperture aligned With said second aperture, a pin extending through said (first and second and third apertures, and removable holding means for said pin located in front of said first aperture so as to be accessible from the front for ease of removal.

7. A freezer according to claim 1 in which the means for ejecting frozen liquid comprises means for twisting the mold about an axis to assist in the release of the frozen liquid from the mold and in which the mold has an integral extension located adjacent said axis extending through the insulating member provided with means for holding the insulating member in contact with the mold.

8. A freezer according to claim 1 having fastening means located along the longitudinal center line of the mold for fastening said insulating member to the mold.

9. A mechanical device according to claim 6 in which the rear portion of the mold and said first aperture are located between the rear portion and the forwardly extending projection and said second and third apertures of said support means.

References Cited by the Examiner FOREIGN PATENTS of 1919 Netherlands.

ROBERT A. OLEARY, Primary Examiner.

N. R. WILSON, Assistant Examiner. 

1. AN AUTOMATIC LIQUID FREEZER INCLUDING A MOLD HAVING WALL PORTIONS FORMING LIQUID HOLDING COMPARTMENTS, MEANS FOR FREEZING LIQUID IN SAID MOLD, A TEMPERATURE RESPONSIVE MEANS IN CONTACT WITH A WALL PORTION ADJACENT ONE OF SAID COMPARTMENTS, AN INSULATING MEMBER SHAPED TO FIT OVER AND OVERLAY SAID TEMPERATURE RESPONSIVE MEANS AND THE ADJACENT WALL PORTION AND A MAJOR PART OF THE WALL PORTION OF ONE OF SAID COMPARTMENTS, AND MEANS RESPONSIVE TO THE TEMPERATURE OF THE TEMPERATURE RESPONSIVE MEANS FOR EJECTING FROZEN LIQUID FROM SAID MOLD. 